Improvement in sewing-machines



4 Sheets-Sheeb 1. W. MARTIN, Jr., D. R. DAWSON & R. ORGHARSewing-Machine.

Pacented Aug. 6.1878.

N PETERS. FHOTO-UTHOGRIFHER, WASHINGTON. D C.

4 Sheets-Sheet; 2. W. MARTIN, Jr., D. R. DAWSON 8v R. ORUHAR.

' Sewing-Machine.

No. 206,743. Patented Aug. 6.1878.

QE WM N-PETERS. PHOTO-UTHOGHAFHEH, WASHINGTON. D O- 4 Sheets-Sheet 3.,Jr., D. R. DAWSON & R. OROH'AR.

W. MARTIN Sewing-Machine.

No. 206,743. Patented Aug. 6.1878.

WITNESS 4 Sheets-Sheen 4. W. MARTIN, Jr., D. R. DAWSON & R. ORGHAR.

Sewing-Machine.

No. 206,743. Patented Aug. 6.1878.

4/ lN\/ENTORS. mm

N. PETERS, PHOTO-LIYNOGRAPHER, WASHINGTON. D O.

UNITED STATES PATENT OFFICE.

WILLIAM MARTIN, JR., DAVID R. DAWSON, AND ROBERT OROHAR, OF DUNDEE,NORTH BRITAIN.

IMPROVEMENT lN SEWING-MACHINES.

Specification forming part of Letters Patent No. 206,743, dated August6, 1878; application filed May 18, 1877: patented in England May 6,1876.

To all whom it may concern:

Be it known that we, WILLIAM MARTIN, the younger, director, DAVIDRUSSELL DAW- soN, secretary, both of Laings Patent Overhead Hand StitchSewing Machine Company, limited, and ROBERT OROHAR, engineer, all ofDundee, in the county of Forfar, North Britain, have inventedImprovements in Laings Overseam Sewing-Machine, of which the followingis a specification:

Our said invention relates to improvements in some of the details ofthat sewing-machine for which Letters Patent were granted to JamesLaing, dated the 27th day of April, 1875, and numbered 162,665.

The invention relates, first, to certain improvements in means foractuating the threadbarrel and threading the needle; second, to meansfor guiding the spiral needle; third, to a driving-cone, arranged in thesame plane as the axis of the barrel-tube, for imparting variablemotion; fourth, to a presser carried inbrackets, within which coiledsprings are arranged, which by their action impart the desired amount ofstress to the presser; fifth, to certain means whereby the rate oftravel of the pitch-feeding chain, and also the degree of tension on thespiral needle, may be regulated.

In order that the overseam sewing machine as constructed with theseimprovements may be properly understood, we now proceed moreparticularly to set forth the system, mode, or manner in or under whichour said improvements are or may be used or carried into practicaleffect, reference being had to the accompanying sheets of drawings, andto the letters and figures marked thereon-that is to say:

Figure 1 of the drawings, hereunto appended, is a front elevation, Fig.4 a plan, and Fig. 5 an end elevation of the overseam sewing-machinehereinbefore referred to, with the improvements constituting our saidinvention shown in conjunction therewith.

As shown by these figures, the improved machine consists of arectangular frame-work, A, supporting at its rearward side a shaft, B,which is rotated by a belt passed round the pulley O of the fast andloose pulleys O D, sit

uate on one end of the shaft. Another pulley, F, is also fixed on theshaft B, and from it motion is communicated by the band E to acylindrical spiral hook or needle, a, round which the band E passes, andwhich is similar in construction to the spiral hook or needle of theoverseam sewing-machine described in the aforesaid specification of thesaid James Laing, it being pointed at the end which first pierces thecloth or fabric, and at its opposite end formed with a hook, by whichthe thread used in sewing is held.

The band E passes from the pulley F round two other pulleys, G, in thedirection shown at Fig. 5 of the drawings, and it is stented by aroller, H, carried in a lever, I, centered on the lower part of theframing A, and weighted at I. A spur-wheel, J, is fixed on the shaft Band geared with a corresponding pinion, K, on the axis of thedriving-cone L, on which a pulley, M is also secured, and by a belt orband passed round the said pulley M the thread-barrel N of the machineand the tube M containing it are rotated. The said tube-M is supportedat the end thereof (marked M) in a solid cylindrical bearing, M made inthe framing of the machine, thereby avoiding the anti-friction rollersemployed to support the corresponding end of the tube M in the machine,as shown and described in the aforesaid specification of the said JamesLain g.

Another part of our invention consists in dispensing with the innerroller employed to guide the needle in the machine, as described in theaforesaid specification of the said James Laing, and providing insteadthereof a fixed inner guide, 0, (seen in detail at Figs. 6 and 7,) whichsurrounds the thread-barrel tube M and is {secured to the front centergable or standard M of the framing A. By this means lateral motion ofthe needle is prevented.

From the driving-cone L rotary motion is communicated by the belt orband P to the front drivingcone Q, the shaft or spindle whereof carriesa clutch-box, b, into which a clutch, c, sliding on a feather on itsshaft is geared while the needle is sewing, and disengaged when it isrequired to supply thread to the :heedle.

At the back of the clutch c a box or cha1nber, f, containing a spiralspring, 0, is formed, and on the extremity of the spindle of the clutchc a tangent-screw, (I, is secured and geared with a worm-wheel, c, fixedon a shaft, g, lying at right angles to the axis of the cone Q. On theshaft 9 we prefer to fix a double cam, R, the contour of each section ofwhich is approximately that of an involute curve having a deep step, ora single cam may he employed.

The curved surface of the cam bears, while the needle is sewing, upon apin or tumbler, 1:, carried in a slot or hole made in the lever S, whichis centered at its lower end on a bracket or foot-step, T, and formed atits upper extremity with a toothed quadrant, which gears into ahorizontal rack formed at l', Fig. 4, in a saddle, Y, connected to thespindle V of the thread-barrel N, and to a spindle or rod, 2', whichpasses through the bearings of the cone Q and of the tangent-screw d. Onthis spindle or rod the thread drag or tension is and the knife I, bywhich the end of the thread is severed from the cloth or fabric beingsewed, as in the machine described in the aforesaid specification of thesaid James Laing, are carried. The saddle V is fiu'ther connected to arod or spindle, m, at one end of which a disk or striker, a, is fixed,and in connection with the said striker an apparatus consisting of ahandle or lever, 0, connecting rod or link 12, eccentric q, crank r, andlever s are provided. The eccentric and crank q and r are situate,respectively, at the upper and lower extremities of a vertical rodcarried in a bracket attached to the framing A, while the lever siscentered on a separate rod or pin, t, also carried in the bracket. Thearrangement is illustrated in enlarged detail at Figs. 2 and 3. One endof the lever s is connected to the crank r by a pin, 1', which passesdownward through a slot in it, while the opposite end of the said levers is attached to the clutch c, as seen in plan at Fig. 4 of thedrawings. The threader u, by which the bight or loop of thread isdelivered to the needle, as in the machine described in the aforesaidspecification of the said James Laing, is situate on and projects towardthe needle from the axis of the horizontal needle 0. \Yeights X areattached to the qinulrantlever S, as shown.

The operation of this apparatus, which is employed instead of the screwactuating the thread-barrel N, as described in the aforesaidspecification of the said James Laing, is as follows: \Vhile the needleis sewing with a thread previously supplied to it, the clutches b and care in gear with each other, whereby rotary motion is communicated tothe cam 1tthrough the intervention of the tangent-screw d and worm-wheelc. This motion of the cam R, which is in the direction of the arrow,Fig. 1, forces the lever S backward, which lever, being geared by therack formed on the saddle V with the spindle V of the threadabarrel N,also draws the said barrel backward into its tube M as the threadbecomes unwound therefrom in the manner described in the aforesaidspecification of the said James Laing. This backward motion continuesuntil all the thread has been unwound from the barrel N, at which timethe part 3 of the cam is hearing against the pin or tumbler h. The part3 having passed the. pin or tumbler, the barrel N is again pushed out toits full extent by the weights X drawing forward the lever S, and theclutches b and c are on the said forward motion thrown out of gear witheach other by the striker n acting against the pin r. The attendant thenremoves a new piece of thread from the hook 4, places a loop of it overthe part 1' of the tlireader, and by means of the lever 0 presents theloop to the eye or hook of the needle, at the same engaging the clutchesb and e, which has the effect of again setting in motion the cam R, andthe new piece of thread having been wound on the barrel N, as set forthin the aforesaid specification of the said James Laing, the sewing isproceeded with.

The engaging and disengaging of the clutches and b may be described asfollows: When the lever o is actuated so as to present the thread to theneedle the spindle a is forced upward by the eccentric q, to which it isconnected, and the pin 2- is thereby brought above the level of thestriker n. The lever S being now set free, the spring acting on the backof the clutch cforces the said clutch into gear with the clutch b, andthe sewing is continued until the barrel N has been moved back to theextremity of its rearward stroke, from which it is again brought forwardby means of the weights X, as already described.

The cams It employed vary in extent of travel according to the workrequiring to be sewed; or, in place of the cam, a sliding wedge orinclined surface may be used, which, as it is moved, acts upon the leverS and draws it back, thereby lifting the weight until, sliding out ofcontact with the lever, it affords a sudden relief thereto, so that thelever is drawn forward by the falling of the weights, and thethread-barrel N is again forced out.

The driving-cone Q for the variable motion is, as seen in the drawings,placed in the same horizontal plane as the axis of the tube M of thethread-barrel N, instead of being placed in a higher plane, as shown inthe drawings annexed to the aforesaid specification of the said JamesLaing; and this arrangement permits of a bar or rod being placed alongthe front of the machine to carry the improved presser 6, by which thefabric being sewed is held down on the table and pitch-feeding chain ofthe machine.

The improvement in the presser consists in earring it in brackets 7, atwhose interiors coilsprings 7" are placed, the said brackets beingattached to the bar 8, laid parallel to the length of the machine, sothat when it is desired to move the presser out of contact with thefabric being sewed all that is necessary is for the attendant to liftthe presser. The springs in the brackets 7 force the presser down on thecloth with the requisite stress.

In our machine a finer adjustment of the rate of travel of thepitch-feeding chain 9 is obtained than in the machine described in theaforesaid specification of the said James Laing by the addition offriction-disks 10 and 11 to the spur-gearing 12 and by introducing afriction-clutch, 13, on the shaft 14, that drives the pitch-feedin gchain by which the length of the stitches is regulated, as well as thetension on the spiral needles, that tension being thereby prevented fromattaining an extent which would be dangerous to the needle by virtue ofthe friction-clutch slipping before that degree of tension is reached.

The clutch consists of the plate or disk 13, secured on the shaft 14,and through which screws 16 are passed, these bearing against the loosefriction-disk 10, so as to force it into contact withthe wheel 12, andthe said wheel into contact with the fixed friction-disk 11.

A modification of the invention (shown on the drawings at Fig. 8)consists in dispensing with the reversed cone-pulleys L and Q andemploying friction-plates L and L rotating in opposite directions, fordriving a friction-roller, R between them on a shaft, R at right anglesto the shaft M of the friction-plates, and so that by moving thefriction-roller inward or outward from the axis of the friction-platesthe requisite variable motion is obtained.

Having now described and particularly ascertained the nature of our saidinvention, and the system, mode, or m anncr in or under which the sameis or may be used or practically carried into effect, we would observe,in conclusion, that what we consider to be novel and original, andtherefore claim and desire to secure by Letters Patent, is

1. The combination of cam R, lever S, provided with pin h and toothedquadrant, rack U, spindle V, threader it, lever o, clutches b and 0, anddevices connecting such parts, as and for the purposes set forth.

2. The combination, with the needle of the fixed inner guide 0,thread-barrel tube M, and standard M, as and for the purposes set forth.

3. The combination, with the driving-cone L, of the front driving-coneQ, clutches b and 0, spring 6, tangent-screw d, worm a, threadbarrel N,and connecting mechanism, as and for the purpose set forth.

4. The combination of the presser 6, brackets 7 parallel bar 8, andcoiled springs 7 as and for the purpose set forth.

5. The friction-disks 10 11, spur-gearin g 12, friction-clutch 13, andshaft 14, for regulating the rate of travel of the pitch-feeding chainand the degree of tension on the spiral needle, sub stantially as setforth.

In witness whereof wehave signed our names to this specification in thepresence of the subscribing witnesses.

w. MARTIN, JR. n s] DAVID R. DAWSON. n s.] ROBERT OROHAR. n s.]

Witnesses JOHN DUFF, AUGUSTUS PIRVIN.

